I'm a little bit confused here... A few years ago (somewhere around 2008-2009), she wrote on her personnal web site (janamrazkova.com, now defunct) that she was retiring from modelling to pursue her career as a make-up artist. Several months later, her site went down and she completely disappeared from porn.
Now, those "new" sets are published. I remember early in her career (back in her Pier999 days) that she was dying her hair blond. Could they just have published old sets from that period that were never published before ? Although I will consede that she DOES look much older in those new sets... Bad make-up, perhaps... or may be she just came out of retirement for an unknown reason.
But concerning your point about her plumper pussy, I think it is an optical illusion mostly due to the fact that she is completely shaven in those pictures. If you compare with the few rare shaven pictures of her in her younger days, there is not much of a difference. But I could be wrong...